samane mohamadi; Adel Sepehry; Mohammad Farzam; Hosein Barani
Volume 30, Issue 3 , January 2024, , Pages 457-473
Abstract
IntroductionThe present research on Lycium depressum stocks aims to study the vegetative responses (leaf area, leaf specific weight, leaf specific area, dry weight ratio of root to shoot, dry weight of leaf, stem, and root) of the pasture shrub of Kam Tigh against drought stress and the effect of soil ...
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IntroductionThe present research on Lycium depressum stocks aims to study the vegetative responses (leaf area, leaf specific weight, leaf specific area, dry weight ratio of root to shoot, dry weight of leaf, stem, and root) of the pasture shrub of Kam Tigh against drought stress and the effect of soil amendment on these responses. Materials and methods The experiment was conducted in a factorial design based on a completely randomized design, including the main irrigation treatment at four levels (100, 75, 50, and 25% of crop capacity) and sub-treatment of soil conditioners under semi-controlled greenhouse conditions. The experiment involved five repetitions and 160 pots for each combined irrigation and soil amendment treatment. Sub-treatments of soil conditioners, including Stacosorb hydrogel, were added at 3 grams per kilogram of soil in each pot in the lower part of the plant roots. Mineral Zeolite in 8 grams per pot was placed in the lower part of the plant roots. Nitrobacter was added in the amount of 3 cc in each pot in the upper root area of the plant. Mycorrhiza at 10 grams per pot was added to the lower plant roots. Results and discussionGenerally, a significant difference (p<0.05) was observed in all irrigation levels between the treatments in each soil amendment material. In zeolite with mycorrhiza, the highest stem dry weight and leaf-specific weight were obtained at a 50% irrigation level. With the increase in leaf-specific gravity and drought stress, plant dry weight increased, and proline content decreased in Nitrobacter and mycorrhizal treatment, which differed from the treatment. Measurements of leaf area revealed that leaf area decreased from 1450 mm2 in 100% and 75% irrigation to 900 mm2 in 25% irrigation. This indicated the impact of drought stress on the leaf area. The highest specific weight of leaves at 25% irrigation was related to Nitrobacter with mycorrhiza. This modifier increased the specific weight of leaves from 0.0025 g/m2 at 100% irrigation level to 0.0028 g/m2 at 25% irrigation level. Leaf surface area in Nitrobacter treatment with mycorrhiza during 100% irrigation decreased from 400 mm2/g to 350 mm2/g during 25% irrigation. In hydrogel treatment without mycorrhiza, the dry weight ratio of root to shoot at 100% irrigation level declined from 2 grams to 1.4 grams in 25% irrigation. The dry weight of the leaf decreased from 1.4 g in 100% irrigation to 1.3 g in 25% irrigation. ConclusionsBiofertilizers enhance plant resistance to drought stress by improving vegetative characteristics. Nitrobacter treatments without mycorrhiza, hydrogel, and zeolite with mycorrhiza are recommended for planting this plant due to improved growing conditions. Since the Kam Tig plant is considered a medicinal plant, it can be used as a soil conditioner in the pharmaceutical and medical industries. This will enable better cultivation of the species. All organizations related to the cultivation of Kam Tig species can use the results of this research to enhance cultivation projects.
Parvin Rokhfrooz; Mohammad Farzam; Mohammad KhajeHoseini
Volume 27, Issue 1 , April 2020, , Pages 75-83
Abstract
Times and methods of seed harvesting and seed storage have important effects on seedling viability and establishment. Effects of seed harvesting times and storage duration were tested on seed germination of Krashninkoviaceratoides in the Shahrak-Imam Seed Production Station in Neyshabur Iran. Experiment ...
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Times and methods of seed harvesting and seed storage have important effects on seedling viability and establishment. Effects of seed harvesting times and storage duration were tested on seed germination of Krashninkoviaceratoides in the Shahrak-Imam Seed Production Station in Neyshabur Iran. Experiment treatments were: 1) two methods of cultivation for seed producing stands (rainfed or irrigation), 2) two methods of seed storage (cold room and normal condition), 3) seed scarification and coat removal in 6 times of seed harvesting, and 8 periods of seed storage. All treatments were designed as three independent experiments, and statistical analysis were performed accordingly. For each experiment, four replicates (25 seeds each) were located in a germinator with 14:10 hours light and dark periods. Methods of seed storage (cold room or ambient) did not affected seed germination rate. Rainfed grown stands led to higher germination percent as compared to those growing under irrigation. Seed coat removing significantly reduced germination rate. Under both cold and ambient storage conditions, seed germination rates did not significantly change till 242 days after harvesting; it gradually reduced and reached to zero at 271 days after seed harvest. According to the results of this research, the best time for seed collection is early October, seeds do not need coat removing or cold treatments, as they are able to germinate till 6 months after the ripening stage under the normal room storage conditions.
Mehri Dinarvand; Seyed Bahram Andarzian; Hamid Ejtehadi; Mohammad Farzam
Volume 25, Issue 2 , August 2018, , Pages 388-398
Abstract
Modeling the growth stages of plant species and its relation with environmental factors, especially climatic and edaphic changes, can lead to appropriate management and conservation plans for rangeland rehabilitation and improvement. The objectives of this study were to evaluate the ...
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Modeling the growth stages of plant species and its relation with environmental factors, especially climatic and edaphic changes, can lead to appropriate management and conservation plans for rangeland rehabilitation and improvement. The objectives of this study were to evaluate the AquaCrop model for two species (Medicago polymorpha L., Hordeum murinum subsp. glaucum (Staud.)Tzvelev) in the Shimbar protected area. Therefore, model evaluation was performed based on the data recorded during 2013-2015. Coefficient of determination (R2), absolute and normalized root mean square error (RMSE, NRMSE), Willmott agreement index (d) and Efficiency Coefficient (EF) were used to compare the simulated data with the data of the second year. The evaluation of AquaCrop model for canopy cover and biomass in selected species demonstrated that the model had the necessary efficiency for simulation. The values of R2, EF, and, d recorded for the canopy cover and biomass of Medicago polymorpha and Hordeum murinum subsp. glaucum were near 1. The values of RMSE calculated for canopy cover and biomass were between 1 to 3.7 and 0.03 to 0.23, respectively.